U.S. Pat. No. 5,636,523 discloses an LRC and expander having a rotating jacket, the teachings of which are incorporated herein by reference.
This known LRC, however, has several disadvantages: while the jacket is free to rotate by the liquid ring which is driven by the rotor, the velocity of the rotating casing lags behind the rotor's tips, rendering the flow unstable namely, causing inertial instability, especially when the angular momentum becomes smaller with large radiuses (the angular momentum of a liquid element located at a radius r is defined as the product u·r, where u is the tangential velocity). As the liquid velocity near the jacket follows the jacket's velocity, when the jacket's velocity lags behind the rotor's velocity, the friction, which is formed between the liquid and the jacket and the liquids between the liquid ring and the rotor vanes, will cause instability in the compressor.
Furthermore, in the prior art LRC, the lateral disc-shaped walls of the compressor are stationary. Thus, the liquid ring which rotates around the wet stationary walls, will also generate friction, detracting from the overall efficiency of the compressor.